Beneath the Surface: How an Underground Marathon Is Rewriting the Story of Mining

When you think of mining, what comes to mind? For many, it’s a scene straight out of the past: a shadowy cavern, the echo of pickaxes, danger, grime, and a sense of being far removed from the world above. While this image is outdated, it continues to shape public perception of the mining industry, which has long left those days behind.  

This perception was exactly what the International Council on Mining and Metals (ICMM), BecomingX and Boliden Mines hoped to challenge when they put forth a bold idea: host the world’s deepest marathon, 1,120 meters underground, in Sweden’s Boliden Garpenberg zinc mine.

For Egon Zehnder’s Chris King-Sidney, a self-described non-runner and first-time marathoner, the journey began over coffee with Rohitesh Dhawan, CEO of ICMM. “We were chatting about adventure sports, and he asked, ‘How about running a marathon in a mine?’” King-Sidney recalls. The conversation quickly turned serious: ICMM’s goal was to raise awareness and shift how the world views mining, highlighting the sector’s transformation from the stereotypes of the past to a story of innovation, safety, and community. “Ro asked if I’d be interested in doing the marathon—not just as a personal challenge, but as a way to help tell this new story,” King-Sidney explains. “I’d never run a marathon before, but if I was going to do one, why not make it this one?” 

In addition to being a personal endurance challenge and an opportunity to showcase the reality of modern mining, it was also a charitable endeavor, raising about $1 million for two charities: the BecomingX Foundation, which provides disadvantaged young people in Africa with education and resources to help them succeed, and the Wild at Heart Foundation, which works to compassionately reduce the global stray dog population. 

Fifty-five runners from 18 countries gathered for an unprecedented challenge: 11 laps of a tunnel, battling humidity, temperatures between 25-30°C, gravel floors, and near-total darkness to complete a full marathon underground. Along the way, the runners set two new Guinness World Records. While the elements were tough, for King-Sidney the real test was mental. “Physically, you can train. But running for hours in darkness, with no external stimulation, is where you’re truly tested,” he shares. “I set a goal—don’t stop, don’t walk. The hardest moments weren’t about tired legs; they were about trusting my preparation, embracing the unknown, and not letting fear take over.” 

That willingness to operate outside one’s comfort zone is essential not just for endurance sports, but for growth in any context. “It takes courage, grit, and comfort with ambiguity to attempt something like this. If you don’t push your limits, you never find out what they are. That’s true in leadership as much as it is 1,120 meters below ground.” 

One big form of motivation during the race came from the Boliden team that helped organize the event, ran logistics, safety protocols and cheered all the runners on throughout. “Seeing the excitement in their eyes and knowing we were doing this to showcase their mine and their health and safety practices just gave it a different level of meaning,” King-Sidney said.

A primary objective of the race was to highlight the advanced technology, safety standards, and professionalism that characterize modern mining practices. "If there’s one thing I hope people take away from this experience, it’s that mining truly is a vital pillar of our world’s economy," King-Sidney reflected. "Events like this marathon really show just how far the industry has come. When you pair innovation with a real commitment to safety, you realize what’s possible. and I hope that inspires curiosity and a new understanding." 

As he reflected on the impact of this experience, King-Sidney noted that he hopes there is resonance about this race beyond the finish line and the world records. “I hope it sparks curiosity. People hear about this race and ask, ‘How is that possible?’ And they learn that mining is safer, more innovative, and more essential than they realized.”